title: BST-2/tetherin is overexpressed in mammary gland and tumor tissues in MMTV-induced mammary cancer.
abstract: BST-2 restricts MMTV replication, but once infection has established, MMTV modulates BST-2 levels. MMTV-directed BST-2 modulation is tissue-specific and dependent on infection and neoplastic transformation status of cells. In the lymphoid compartment of infected mice, BST-2 expression is first upregulated and then significantly downregulated regardless of absence or presence of mammary tumors. However, in mammary gland tissues, upregulation of BST-2 expression is dependent on the presence of mammary tumors and tumor tissues themselves have high BST-2 levels. Elevated BST-2 expression in these tissues is not attributable to IFN since levels of IFNα and IFNγ negatively correlate with BST-2. Importantly, soluble factors released by tumor cells suppress IFNα and IFNγ but induce BST-2. These data suggest that overexpression of BST-2 in carcinoma tissues could not be attributed to IFNs but to a yet to be determined factor that upregulates BST-2 once oncogenesis is initiated.
authors.affiliation: Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109, USA. philip-jones@uiowa.edu
authors.forename: Philip H
authors.initials: PH
authors.lastname: Jones
authors.forename: Wadie D
authors.initials: WD
authors.lastname: Mahauad-Fernandez
authors.forename: Marisa N
authors.initials: MN
authors.lastname: Madison
authors.forename: Chioma M
authors.initials: CM
authors.lastname: Okeoma
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis*; D005260:Female; D054884:Host-Pathogen Interactions; D006801:Humans; D008297:Male; D008321:Mammary Glands, Animal / Q000473:pathology*; D008325:Mammary Neoplasms, Experimental / Q000473:pathology*; D008324:Mammary Tumor Virus, Mouse / Q000472:pathogenicity*; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D011247:Pregnancy; D012192:Retroviridae Infections / Q000473:pathology*; D014412:Tumor Virus Infections / Q000473:pathology*; D000074010:Bone Marrow Stromal Antigen 2
chemical_list: D015703:Antigens, CD; D008562:Membrane Glycoproteins; C513868:BST2 protein, mouse; D000074010:Bone Marrow Stromal Antigen 2
keywords: AKT; BST-2; Bone marrow stromal cell antigen 2; CCL3; Cancer; Epithelial cells; FACS; Fluorescence activated cell sorting; Human breast cancer; MIP1-α/CCL3; MIP1α; Macrophage inflammatory protein 1-alpha; Mammary gland; Mouse mammary tumor virus; NMuMG; Normal murine mammary gland; PI3K; Phosphoinositide 3 kinase; Tetherin; Transformation; Tumor